Modular valve system

ABSTRACT

The invention relates to a modular valve system comprising at least one valve housing ( 40 ) having rate quantities that are standardised on its opposite ends ( 38, 42 ), both on the inner peripheral side and on the outer peripheral side and inside the housing ( 52 ), for applying other valve components, such as a valve piston ( 46 ). at least one energy accumulator ( 26 ), a pilot-controlled element, and at least one fluidic connection, or for fixing the valve embodied in the form of a screw-in cartridge to other components.

The invention relates to a modular valve system, especially one which may be built with valves known under the technical concept “pilot-controlled pressure relief and pressure control valves.”

Pressure relief valves usually are valves whereby the input pressure is restricted, in that the functional element, closed while at rest, opens the output to the container when the reset pressure is reached. This occurs as a result of opening in opposition to a closing force of a closing element. In the case of pilot-controlled pressure relief valves the pressure of the medium selected by a pilot valve is applied to the closing element. As a result, the difference in pressure between beginning and end of opening is very small. Such pilot-controlled pressure relief valves represent the most common protection feature of all-hydraulic systems.

Pressure control valves, also designated as pressure reduction valves, are ones in which the lower output pressure (secondary pressure) is kept constant, while the input pressure (primary pressure) is variable. Such pressure control valves as well may be pilot-controlled and are frequently used for pressure reduction of large fluid flows.

Manually operated pilot valves, but electrically operated ones as well, are used for the pilot control referred to, the latter being actuated by a magnet, usually one in the form of a proportional magnet system. The respective magnets may be provided with emergency pressure actuation and thus allow manual resetting of the valve if the magnets fail. In addition, so-called switching magnets, proportional magnet systems, with inverted characteristic curves in particular, have been disclosed, that is, an inverse effect is achieved as with a known proportional magnet system; for example, when current does not flow through the proportional magnet, the valve is kept in its closed position (so-called fail-safe applications).

In the known solutions the pressure relief and pressure control valves are still designed individually for each application and adapted to the respective fluid flows to-be controlled. This results in a multiplicity of valves with a multiplicity of various valve structural components and pilot control elements, this in turn resulting in correspondingly high production costs. When a valve is damaged it often must be replaced by a complete new valve; storage of individual components would be too costly, in view of the large number of structural components employed.

On the basis of this prior art the object of the invention is to create a new valve concept which makes it possible to aid in preventing the disadvantages described, and especially in lowering the costs of production and maintenance of valves. An object such as this is attained by means of a modular valve system having the characteristics specified in patent claim 1 in its entirety.

The modular valve system claimed for the invention is provided with at least one valve housing which is characterized at its opposite ends, on both the interior and exterior surfaces and in the interior of the housing, by rated values for mounting of additional structural valve components such as a valve piston, at least one energy accumulator, a pilot control element (pilot valve), and at least one fluid connection or connection for fastening a valve in the form of a screw-in cartridge on other structural components (valve block).

The total valve is constructed on the basis of a standardized valve housing the rated values of which are adapted to predominant fluid flows and fluid amounts, in that the pilot control element (pilot valve) may be modified especially as a function of the specific application, so that a manually operated pilot control may be provided for one type of primary valve structural groups, but also one with proportional magnets and without emergency pressure actuation and with or without inverted characteristic curve and switching pattern. The rated values of the other valve components, such as the valve piston and the energy accumulator (pressure spring) acting on the valve piston, may also be standardized with respect to their values and adapted to the specific valve housing. A small number of structural components, the rated values of which vary with the predominant fluid flows, may thus be used to control a multiplicity of applications in fluid technology, and especially to build and maintain in modular form the pressure relief and pressure control valves frequently required.

Other advantageous embodiments of the modular valve system claimed for the invention are specified in the other dependent claims.

The modular valve system claimed for the invention is described in detail in what follows with reference to the drawing. Of a multiplicity of options

FIG. 1 illustrates four different structures of a pilot-controlled pressure relief valve with pre-assigned rated values;

FIG. 2 illustrates four different structures of a pilot-controlled pressure control valve with pre-assigned rated values.

The configuration of FIGS. 1 and 2 is such that the respective pilot control stage in the form of a pilot valve is illustrated in section I, the pilot control stage in the form of the primary valve proper in section It, and the complete valve consisting of stages I and II, along with the valve switching symbol customary in the literature, in section III. All the components shown in FIG. 1 are those of a pressure relief valve and all the components shown in FIG. 2 those of a pressure control or pressure reduction valve.

All the pilot valves illustrated in I are identical both in the embodiment shown in FIG. 1 and in that shown in FIG. 2. A manually operated pilot valve 10, an electrically operated pilot valve in the form of a proportional magnet 12, a proportional magnet 14 with emergency pressure actuation 16, and a proportional magnet 18 with inverted characteristic curve in relation to embodiments 12, 14 are shown from left to right as viewed in the line of sight to the figures.

The manually operated pilot valve 10 has a valve seat 20 and a valve element 22. The valve element 22 rests against an energy accumulator in the form of a pressure spring 26 the closing force of which may be assigned by way of a resetting element 28 and is guided in an adjustment housing 30. The closing force may be assigned manually by way of a hexagonal head screw 32 with retaining ring 34. Such manually adjustable pilot valves 10 are of the state of the art, and accordingly will not-be described in detail here.

If the individual components referred to are completed along the assembly line 36, the pilot valve as thus completed may be screwed into one end 38 of the valve housing 40. Another energy accumulator in the form of a pressure spring 44 is introduced from the other end 42 of the valve housing on one end of which the main piston 46 rests and on the other end of which there rests on a multipart closing element 50 which may be screwed into the lower free end 42 of the valve housing 40. To this extent the primary control stage II and thus the primary valve proper is standardized in the form of a pressure relief valve and, as the other assembly lines 36 demonstrate, appropriately modified pressure springs 26 and resetting elements 28 are used while the valve elements 22 and pilot chambers 20 remain unchanged in order to obtain modified pressure relief valves having appropriately modified pilot control stages I in the versions indicated on different switching magnets 12, 14, and 18.

Thus, the pressure relief valves shown in III which have the customary switching symbol reproduced on their lower side on the basis of their characteristics may be obtained. If the complete total valve III is to be used under the modular valve system claimed for the invention to control a different fluid volume stream, the rated values at the valve housing 40 are to be correspondingly modified, especially with respect to the interior and circumferential side at the opposite ends 38 and 42 and with respect to the housing interior 52.

As is shown in FIG. 2, the structure of the pilot pressure control valve is selected accordingly. In particular, the pilot control stage I is essentially the same as that of the pilot control stage I in FIG. 1; in the manually operated pilot valve 110 another energy accumulator in the form of the pressure spring 154 which engages the opposite side of the pilot chamber 120 is added in addition to the energy accumulator in the form of the pressure spring 26. The structure in question is of the state of the art and will not be discussed in detail at this point. In addition, to the extent that the components in the modified embodiment in FIG. 2 correspond to the valve design shown in FIG. 1 the same reference numbers are used, with the exception that each is increased by 100. What has been stated also applies to this extent to the embodiment of a pressure control valve as shown in FIG. 2.

In contrast to the pressure relief valve, in the embodiment shown in FIG. 2 the control piston 146 has a nozzle element 156, while in other respects the valve housing 140 is adapted with respect to its fluid connections to the functions to be performed by a pressure control valve. In this instance as well the valve housing 140 with its structural valve components is to be adapted to the extent that the fluid flows to be controlled vary with respect to volume and/or pressure. As a rule, however, the same pilot control stages indicated in FIG. 1 are employed in the valve design illustrated in FIG. 2.

The average expert in the field of valve technology may find it surprising that he can employ only a few basic components to develop a multiplicity of valve designs with different rated values without the need for developing his own structure on each occasion. The modular valve system claimed for the invention permits configuration of each valve obtained as a screw-in cartridge, so that both the pressure relief and the pressure control valves may be fastened on other structural components, such as ones in the form of a valve block in an all-hydraulic system. 

1. A modular valve system having at least one valve housing (40; 140) with standard rated values at its opposite ends (38, 42; 138, 142) on both the interior and exterior circumference and in the interior of the housing (52; 152) for mounting of additional structural valve components such as a valve piston (46; 146), at least one energy accumulator (26; 126), a pilot control element, and at least one fluid connection or connection for fastening the valve configured as a screw-in cartridge to other structural components.
 2. The modular valve system as claimed in claim 1, wherein the valves which may be built with the components of the system are pressure relief and pressure control valves having a pilot valve (10, 12, 14, 18; 110, 112, 114, 118) as pilot control element.
 3. The modular valve system as claimed in claim 1 or 2, wherein the pilot valve (10, 110) may be operated manually or electrically and wherein switching magnets, preferably proportional magnets, are used for electric actuation.
 4. The modular valve system as claimed in claim 3, wherein the magnets are in the form of proportional magnet systems with and without emergency manual actuation and/or with inverted switching pattern.
 5. The modular valve system as claimed in one of claims 2 to 4, wherein the respective pressure relief valve having as valve piston a main piston (46) which rests against a pressure spring (44) in the valve housing (40) so as to be longitudinally displaceable and wherein the main piston (46) is retained opposite the end facing away from the pilot valve (10, 12, 14, 18) by way of a closing element (50) in the valve housing (40).
 6. The modular valve system as claimed in one of claims 2 to 4, wherein the respective pressure control valve has as valve piston (146) a control piston with which a nozzle (156) is integrated and wherein the control piston rests against the respective pilot valve (110, 112, 114, 118) by means of a pressure spring (154) and otherwise is guided so as to be longitudinally displaceable in the valve housing (140). 